Kepler-22b is the first planet discovered inside the habitable zone of a Sun-like star. This artist’s conception from 2011, shows the first planet that NASA’s Kepler mission has confirmed to orbit the region around a star where liquid water, a requirement for life on Earth, could exist. This exoplanet is 2.4 times the size of Earth, making it the smallest yet found to orbit in the middle of the habitable zone of a star like our Sun.
At the time scientists did not know if the planet has a predominantly rocky, gaseous or liquid composition. It’s possible that the world would have clouds in its atmosphere, as depicted here in the artist’s interpretation.
Image Credit: NASA/Ames/JPL-Caltech